The key to breaking a pileup is listening and learning - before you call.

First - you need to hear them.

Unless you can hear the DX station and hear them well enough to tell exactly what they’re doing, there’s no point calling. And once you can hear the DX station well, you need to determine where they are listening. This is easy if they are operating simplex. But, more than likely, for any reasonably sized pile-up, they will be operating split.

Many modern transceivers allow listening on two frequencies at the same time, so the next step will be easy: listen to the DX station on their transmitting frequency and find the station they’re working on their receiving frequency.

Depending on propagation however, you may not be able to hear who the DX station is coming back to, so keep listening and tuning - you’ll eventually determine whether the DX station is staying in one spot or tuning around in the pileup. Of course, the best frequency to be when you start calling is on the exact spot where the DX station was listening for their last contact.

Only then is it time to call. BTW, if you need to tune up your amplifier, move somewhere else before doing so.

Keep your calls short:

Give your full call sign - then go back to listening. Sometimes you’ll need to repeat this cycle two or three times. Once the DX station comes back to someone, there's no sense continuing to call - unless the station called is you.

And even if you start calling, don't stop listening.

Who is the DX station working? Stations in your area, or another continent? Perhaps they’re working callers from all over. Listen closely.

Who are the stations the DX station responds to? Are they the earliest, or the strongest callers, or is the DX station picking callers later in the pileup when the calls die down? Are “tail-ender” callers being worked or are they being ignored? Determine the pattern the DX station is using and use that information to adjust the timing and placement of your calls.

Be patient:

Pileups can be huge random events, and if you keep listening and carefully calling, you'll likely get through. It may be on the first or second call, or it could take a half hour of calling. Don't get discouraged. And remember, despite your best efforts, some DX will get away. Propagation will change, or the station will switch bands or modes, or may even QRT. You have no control over that, so don't worry about it. Importantly - don't let it affect your performance.

Careful listening makes a big difference. It will tell you where to transmit, and when.

Get the Rhythm:

Listen to get the rhythm of how exchanges are being made, and what information is being exchanged. Is the DX station giving only their call sign and a “5-9” signal report? Or, do exchanges include name and other details? Follow suit. If only call sign and signal report, refrain from giving your QTH and/or name.

Remember - listen, listen - and listen some more. You will pick up clues which will help you make the contact. The DX station may be "running by the numbers", or by areas. You might notice QSB on the band and be able to make the contact when the propagation fluctuations are on the rise. Learn by listening and take note. By listening to a DX station over time you’ll learn about propagation, not just to and from the DX station, but also to other areas of the world.

Listening will help you make the contact properly. You’ll hear good operating practices - and unfortunately, bad ones. Don't imitate the bad ones. Through close listening you’ll learn things from a perspective which might not otherwise be apparent.

Phonetics and Exchanges:

Listen to how different amateur radio operators make their contacts. Some use techniques with a winning pattern, while others have a hard time.

"Tail-ending" - quickly throwing in your call sign right after the non-DX station is about to clear with the DX station - is a technique which can be successful. But be careful not to cause QRM. And know that some DX stations don't like that practice, considering it rude. Remember, when you do this, you're essentially interjecting yourself into another conversation which may interrupt the rhythm of the communication.

During a pileup, it sometimes helps to get your call sign in first - right after the DX stops transmitting. However, more often, you’ll need to let the "roar" of the pileup die down, and just about the time most stations stop transmitting - but before the DX picks a call sign - say your call sign. That's sometimes the best time to call. Listen to see whether the DX station regularly picks up the first station that calls, or if they let the pileup settle down for the most part, and then pick a call sign near the end, when most stations have stopped calling.

In many cases, "Big Gun" stations will overpower the pileup and make the contact. But if you’re a "little pistol", running 100W to a wire antenna, smart timing can help you win out. 

Sometimes, you should say your call sign only once, and sometimes you should say it once, wait a few seconds, then say it again. Avoid calling continually though, because you risk becoming a nuisance, not only to the DX station, but also to everyone - especially if you call when the DX station returns to someone else.

So, it’s important to observe the timing, pace and flow of exchanges.

Sometimes, the DX station may only get a part of a call sign, and may say: "the India Tango station" or just: "station with Tango". That's when you would give your call sign again, providing they gave a portion of your call sign. However, there may be other stations who also have a letter of your call sign, so don't call, especially if you know it’s the portion of a suffix belonging to another station.

If you hear the DX station ask for "the Papa Zulu station" and no one answers, you might be tempted to throw your call sign in after a second or two. This is a bit of a gamble. If you do throw your call in, you’re sticking your foot in the door - and that door may either open - or it may slam shut.

Finally, when pileups grow too large, DX stations often may start operating by the numbers, or by country, or by zone. Note also, some DX stations may not operate “split” when they perhaps should. This may be because they lack the capability, or the necessary knowledge or experience.

Always remember - the DX station is "boss" of the pileup - they run it as they see fit.

Good hunting!